The Laboratory Animal Resource (LAR) is responsible for laboratory animal care and use primarily by investigators at RPCI with peer-reviewed funding. In June 2002, the Resource was granted full accreditation by the Association for the Assessment and Accreditation of Laboratory Animal Care International (AAALAC International). The Resource provides specialized animal husbandry; veterinary medical care; animal health surveillance; diagnostic laboratory facilities; research technical services and resources including genetically defined mice; a surgical program and technician; and faculty training in support of more than 150 Institute Animal Care and Use Committee-approved animal use protocols. Additional services include polyclonal antibody production in rabbits, hybridoma ascites production and collection in mice, and inbred and immune-deficient rodent production. Daily animal inventories of 21,000, include a variety of rodent species, rabbits, dogs and occasionally farm animals. The Resource Director is a New York State licensed veterinarian who has been trained in pathology (PhD) and is Board-Certified in Laboratory Animal Medicine (ACLAM). Fifteen members of the technical staff are certified through the Certification and Registry Board of the American Association for Laboratory Animal Science (AALAS). The Laboratory Animal Resource is located in the four-story 39,000 nsf vivarium within the Medical Research Complex (MRC), which opened in 1998. Additional newly renovated space is available in the Cancer Cell Center, for a total of approximately 47,000 nsf. Laboratories for work with gene knockout and transgenic technologies in mice are immediately adjacent to animal holding rooms. Continued support through the CCSG will permit the Resource to provide a standard of care and use that meets or exceeds applicable state and federal standards, maintain full AAALAC International accreditation, and furnish investigators with a comprehensive program for safe, appropriate and cost-effective research animal use.